Williams syndrome is a rare genetic condition characterized by unique physical features, delays in cognitive development and potential cardiovascular problems. Children born with Williams syndrome can have a normal life expectancy but may develop side effects from the condition that can affect their prognosis.
Williams syndrome, also known as Williams-Beuren syndrome, is a rare, neurodevelopmental, genetic condition characterized by many symptoms including unique physical features, delayed development, cognitive challenges and cardiovascular abnormalities. Williams syndrome may cause poor growth in childhood, and most adults with the condition are shorter than average. Williams syndrome can also cause endocrine concerns like having too much calcium in your blood and urine, an underactive thyroid and early puberty.
Williams syndrome usually occurs when someone is missing a small piece of chromosome 7. This means that most people with Williams syndrome have not inherited the condition from a parent. People with Williams syndrome have a 50% chance of passing the condition on to their children.
Williams syndrome is a rare condition that occurs in an estimated 1 in every 10,000 births in the United States.
As your child grows, they may face challenges as a result of their diagnosis, but they can reach their full potential with early intervention and treatment. Children may have birth defects involving their heart or blood vessels around it that sometimes need surgery to correct. They will need routine blood and urine tests to keep their kidneys healthy. They often sit and walk a bit later than other children due to loose joints. Often, children with Williams syndrome have strong verbal and communication skills, which could mask delays to their cognitive abilities, which are common in Williams syndrome-like learning numbers and letters, differentiating between real and abstract and their ability to understand the space between objects. Most children with Williams syndrome have an excellent long-term memory but may experience attention-deficit/hyperactivity disorder (ADHD).
A deletion, or missing piece, of a region on chromosome 7 causes Williams syndrome.
In our bodies, we have 46 chromosomes total, arranged into 23 pairs. We inherit one copy of a chromosome in each pair from our parents. Within our chromosomes are segments of DNA (genetic information) known as genes. Our genes are our body’s instruction manual that tells it how to form and function.
People with Williams syndrome are missing a portion of chromosome 7, which is made up of several genes. Since your genes are an instruction manual to your body, if you're missing chromosomes, your instruction manual is missing a few pages that describe how chromosome 7 should function. The missing pages in your instruction manual cause symptoms of Williams syndrome.
Williams syndrome may cause symptoms that range in severity. Not all people with Williams syndrome will have the same set of symptoms.
Symptoms of Williams syndrome include:
Many of the symptoms of Williams syndrome occur in other conditions that are not Williams syndrome and could lead to multiple diagnoses.
Symptoms of Williams syndrome can cause delays for children to reach developmental milestones, which are things that your child can do by a certain age. Developmental milestones showcase how your child thinks, learns, speaks, plays, moves and behaves. Williams syndrome can delay milestones including:
One of the more serious symptoms of Williams syndrome is cardiovascular disease. The narrowing of various blood vessels near the heart is common during fetal development (stenosis), which can lead to increased blood pressure, arrhythmia (irregular heartbeat) and ultimately cardiac failure. Cardiac involvement is often one of the first signs that your child may have Williams syndrome.
A symptom of Williams syndrome is unique physical characteristics that are present when your child is born including:
The condition is typically diagnosed when your child is a baby or early during childhood. If your healthcare provider suspects your child has Williams syndrome, they will provide a physical examination of your child, followed by a genetic test, which is a blood test that identifies gene differences.
Often, your healthcare provider may ask for additional tests to confirm the diagnosis and check the symptoms of the condition. Other tests include:
If someone has Williams syndrome based on physical findings and/or a positive genetic test result, your healthcare provider will work with appropriate specialists to help explain the diagnosis to the individual and their family, especially a genetic counselor.
Your provider will discuss condition management recommendations based on the diagnosis. Although there is no cure for Williams syndrome, it is important to identify and treat the side effects that can occur with this condition. Treatments and interventions must be based on the unique needs of each individual including:
Since Williams syndrome is a genetic condition caused by a chromosome change, not inherited from a parent, there is typically no way to prevent it. If you are planning on becoming pregnant and want to understand the risks of having a child with a genetic condition, talk with your healthcare provider about genetic testing.
Williams syndrome cannot be cured, but treatment is available to manage symptoms. It's important to seek a medical evaluation by your healthcare provider to receive a diagnosis, followed by visits to a specialist as needed to address any symptoms or side effects. Most people with Williams syndrome have a normal life expectancy, but some may have a reduced life expectancy due to complications of the disease (such as cardiovascular problems). Oftentimes, people with Williams syndrome will need additional support as they grow into adults.
If your child receives a Williams syndrome diagnosis, it's best to offer them as much love and support as you can. They will likely need to schedule regular visits with their healthcare provider and specialists to treat any symptoms of the condition that may arise, especially cardiovascular side effects. Your child might need to enroll in a special education program to address any challenges they might face in the classroom. Be patient with your child as they grow and adapt to the world around them at their own pace.
You should visit your child’s healthcare provider if they:
If you notice your child shows signs of heart (cardiovascular) disease, visit the emergency room immediately. Symptoms of cardiovascular disease include:
A note from Cleveland Clinic
Although Williams syndrome is not contagious, your child’s friendly, outgoing personality is infectious. Always provide support to your child, because a new diagnosis can be overwhelming. Some people find that it helps to discuss their questions or concerns with experts, other individuals with Williams syndrome or parents who have children with Williams syndrome.
Last reviewed by a Cleveland Clinic medical professional on 12/10/2021.
Learn more about our editorial process.